JPH0434204A - Piston type oscillatory actuator - Google Patents

Abstract

PURPOSE:To increase output torque by providing outer side and inner side pistons in a cylinder tube on one side of an output shaft, forming the piston shaft of the former in a cylindrical shape, and converting rectilinear reciprocating motion of respective pistons to oscillatory rotating motion. CONSTITUTION:When pressurizing fluid flows into a working chamber C2 from a fluid port 8 and fluid in a working chamber C3 is exhausted from a fluid port 9, a piston 11 is pressed so as to separate from an output shaft 2, fluid enters a working chamber C1 from the working chamber C2 through a fluid passage 21, and pushes in a piston 10 so that it can approach the output shaft 2. A pinion gear 14 is turned by the rack gear 13a of a driving bar 12a and the rack gear 13b of a driving bar 12b, and the output shaft 2 rotates clockwise. When pressurizing fluid flows into the working chamber C3 from the fluid port 9 subsequently and fluid in the working chamber C2, C1 is exhausted from the fluid port 8, the output shaft 2 rotates counter clockwise, and the output shaft 2 performs oscillator rotating motion repetition thereof. It is thus possible to improve output in a miniature size.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention provides a single-cylinder type piston-type oscillator that converts the linear reciprocating motion of a piston that receives working fluid pressure into an oscillating rotational motion. Regarding dynamic actuators.

(Prior art) In a piston-type swing actuator, the piston in the cylinder receives the energy of the working fluid and can generate a swing rotational motion on the output shaft. It is possible to perform opening/closing operations such as opening/closing valves.

This piston type swing actuator includes a double cylinder type in which a piston is installed in each of two cylinders that sandwich the output shaft, and a double cylinder type in which a piston is installed in each cylinder on one side of the output shaft. There is also a single cylinder type.

FIG. 14 shows a conventionally known single cylinder type piston type swing actuator.

In this figure, a piston 42 is built into a cylinder tube 41 provided on one side of an output shaft 40 so as to be able to reciprocate in the left and right directions. A rack gear 43 extending toward the output shaft 40 is protruded from the front inner surface of the piston 42 , and this rack gear 43 is attached to a pinion gear 4 fixed to the output shaft 40 .
It engages with the front part of 4. Further, the guide center shaft 45 protruding from the rack gear 43 that meshes with the front part of the pinion gear 44 is connected to a center hole 45 bored in the other side wall surface of the tube.
It is inserted freely into the .

The cylinder tube is provided with two working fluid ports 47 and 48 through which working fluid flows in and out.
The working fluid port 47 communicates with a first working chamber 49a surrounded by the inner wall surface of the tube and the outer surface of the piston 42.
communicates with a second working chamber surrounded by the inner wall surface of the tube and the inner surface of the piston 42.

In the swing actuator having this configuration, when pressurized fluid flows into the second action chamber 49b from one working fluid port 47, this pressurized fluid presses the inner surface of the piston 42 and moves the piston 42 in the direction of the arrow ( (outward direction).

Along with this, the rack gear 43 rotates the pinion gear 44, and the output shaft 40 rotates clockwise by the outward stroke of the piston. At this time, the working fluid in the first working chamber 49a is forcibly discharged to the outside from the working fluid port 48.

Subsequently, pressurized fluid flows from the working fluid port 48 into the first working chamber 4.
When flowing into the interior of the piston 9a, the pressurized fluid presses the outer surface of the piston 42 and causes the piston 42 to move straight inward. Accordingly, the output shaft 40 rotates counterclockwise by the return stroke of the piston 42. At this time, the working fluid in the second working chamber 49b is forcibly discharged to the outside from the working fluid port 47.

This operation is repeated, and the output shaft 4o performs an oscillating rotational motion.

(Problems to be Solved by the Invention) By the way, the conventional swing actuator described above is configured to receive the working fluid pressure on the inner or outer surface of the piston 42 to generate a swing rotational motion in the output shaft 40. Therefore, if the fluid pressure is the same, the output torque of the output shaft 40 is determined by the area of the piston surface, and swing actuators with the same piston area can only obtain approximately the same output torque.

Therefore, it has been difficult to realize a compact and high-output swing actuator with conventional swing actuators.

The present invention was proposed in order to solve these problems, and an object of the present invention is to provide a piston-type swing actuator that can obtain twice the output torque even if the cylinder cross-sectional area is the same.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, a piston-type swing actuator according to the present invention corresponding to claim (1) is provided with a cylinder tube on one side of the output shaft, and a cylinder tube inside the cylinder tube. An outer piston and an inner piston whose inner surface faces the output shaft side are provided so as to be able to reciprocate, one end of a cylindrical piston shaft is fixed to the outer piston in the cylinder tube, and one end of the cylindrical piston shaft is connected to the outside. A first working chamber facing the outer surface of the piston is opened, the cylindrical piston shaft is slidably and airtightly passed through the inner piston, and the other end of the cylindrical piston shaft is opened to face the inner surface of the inner piston. A first drive bar extending toward the output shaft is fixed to the other end of the cylindrical piston shaft, and a second drive bar extending toward the output shaft is fixed to the inner piston. death,
One of the conversion mechanisms that engages with each other and converts linear reciprocating motion into oscillating rotational motion is attached to the first and second drive bars.
The other one of the conversion mechanisms is attached to the output shaft, and the linear reciprocating motion of each piston is transmitted to the output shaft as an oscillating rotational movement via the first and second drive bars and the conversion mechanism, A first working fluid port through which pressurized working fluid flows in and out is provided in communication with the second working chamber and the first working chamber connected by the cylindrical piston shaft, and a first working fluid port through which pressurized working fluid flows in and out is provided. It is characterized in that the second working fluid port is provided in communication with the third working chamber between the outer piston and the inner piston.

Further, in the rocking actuator according to the present invention corresponding to claim (2), a coil spring is provided in the third action chamber to elastically bias the outer piston and the inner piston in a direction in which they are separated from each other. It is characterized by opening the working fluid port to the atmosphere.

Further, in the piston-type swing actuator according to the present invention corresponding to claim (3), a coil spring is provided in the first action chamber to resiliently bias the outer piston inward, and
It is characterized by opening the working fluid port to the atmosphere.

Further, in the piston-type swing actuator according to the present invention corresponding to claim (4), the tip of the first drive bar is
It is fixed to a piston that reciprocates in a straight line in an auxiliary cylinder tube provided on the other side opposite to the cylinder tube,
A coil spring for biasing the piston inward is provided in a fourth working chamber on the outer surface side of the piston, and an opening communicating with the fourth working chamber is formed in the auxiliary cylinder tube,
The present invention is characterized in that this opening and the second working fluid port are opened to the atmosphere.

(Function) According to the configuration corresponding to claim (1) described above, the pressurized working fluid supplied from the first working fluid port flows through the first working chamber connected to the second working chamber by the cylindrical piston shaft. As the fluid pressure flows into the working chamber, the fluid pressure acts on the inner surface of the inner piston and the outer surface of the outer piston, causing the pistons to move linearly toward each other.

As a result, the output shaft coupled to tJl and the second drive bar is rotated in one direction by the forward stroke of the piston by the conversion mechanism.

Subsequently, when the working fluid is discharged to the outside from the first working fluid port and the pressurized working fluid is supplied to the third working chamber from the second working fluid port, the fluid pressure is increased between the outer surface of the inner piston and the outer piston. These pistons move straight away from each other.

As a result, the output shaft is rotated in the other direction by the piston's return stroke by the conversion mechanism.

These operations are repeated, and the output shaft performs a swinging rotational motion.

Further, in the configuration corresponding to claim (2), the return linear movement of each piston can be performed by the elastic force of the coil spring provided in the third action chamber.

Further, in the configuration corresponding to claim (3), the outward linear movement of each piston can be performed by the elastic force of the coil spring provided in the first action chamber.

In addition, in the configuration corresponding to claim (4), the linear movement of each piston in the return path can be performed by the elastic force of the coil spring provided in the fourth action chamber (Example) Hereinafter, implementation of the present invention will be described. An example will be explained in detail based on the drawings.

The external perspective view of FIG. 1 shows an embodiment of a single cylinder type swing actuator according to the present invention, FIG. 2 is a plan view thereof, and FIG. 3 is a front view thereof.

In these figures, the cylinder tube 1 is hermetically fixed with bolts to one side of the housing 3 where the output shaft 2 is assembled, and the central guide shaft 4 is slid onto the other side of the housing 3. A freely supported support plate 5 is hermetically fixed with bolts. The output shaft 2 is shown as A in Fig. 4.
- The upper plate part 3a of the housing 3 as shown in the longitudinal cross-sectional view on the A line.
The output shaft 2 is rotatably attached to the lower plate part 3b via upper and lower bearings, and a stopper piece 6 is fixed to the base of the output shaft 2 protruding from the upper plate part 3a. When the output shaft 2 swings and rotates, the stopper piece 6 rotates until it comes into contact with the left and right stoppers 7a, 7b on the top surface, so that the swing range of the output shaft 2 can be restricted by these stoppers 7a, 7b. It has become.

Further, on the front side of the actuator, a working fluid port (opening) 8 and a working fluid port (opening) 9 through which working fluid flows in and out are provided in the housing 3. Of these, the working fluid port (opening) 9 is extended toward the cylinder tube 1 side via a conduit a, and an opening 9a is provided at its tip. Although the working fluid may flow directly into and out of the cylinder tube 1 from this opening 9a, in this embodiment, this opening 9a is closed with a plug, and the working fluid is passed from the working fluid port 9 to the cylinder tube 1 through the conduit a. The working fluid is allowed to flow in and out of the 1.

Next, the internal structure of this swing actuator is shown in Fig. 5B.
The description will be made based on a sectional view taken along line -B. This swing actuator is of a double action type, and uses a binion gear and a rack gear as a conversion mechanism that converts the linear reciprocating motion of the piston into rotational motion.

Inside the cylinder tube 1, outer and inner pistons 10.11 are assembled so as to be able to reciprocate in the left and right directions, and a drive bar 12a that extends toward the output shaft 2 is provided on the front part of the inner surface of the inner piston 11. and this drive bar 1
The rack gear 13g formed inside the output shaft 2
The front part of the pinion gear 14 is fixed to the central part of the shaft. A guide center shaft 4 extending toward the support plate 5 is fixed to the L-shaped bent end of the drive bar 12a, and the guide center shaft 4 is connected to the center hole 5A of the support plate 5.
It is slidably inserted airtightly into the housing 3
A rotation stopper T1 of the drive bar 12a is attached to the front part of the drive bar 12a, and the slide of the drive bar 12a in the left and right direction is guided by this rotation stopper T1.

In addition, a drive bar 1 is provided at the rear of the output shaft 2's binion gear 14.
A rack gear 13b formed inside the drive bar 12b meshes with the drive bar 12b, and a cylindrical piston shaft 15 extending toward the cylinder S is fixed to the L-shaped bent end of the drive bar 12b. The piston shaft 15 slidably and airtightly passes through the center hole 16 of the inner piston 11, passes through the outer piston 10, and is fixed to the outer surface of the piston 10. A rotation stop T2 for the drive bar 12b is attached to the rear part of the housing 3, and the movement of the drive bar 12b in the left-right direction is guided by this rotation stop T2.

One end cylinder 17a of the cylindrical piston shaft 15 opens into a first working chamber C1 surrounded by the inner wall surface of the cylinder tube 1 and the outer surface of the outer piston 10.
The other end side cylindrical opening 17b of 5 opens into a second working chamber C2 surrounded by the inner wall surfaces of the tube 1 and the housing 3, the inner surface of the inner piston 11, and the inner wall surface of the support plate 5.

In addition, the inner wall surface of the cylinder tube 1 and both pistons 10.1
The space surrounded by 1 is a third action chamber C3.

Here, the reference numeral 19 is an O-ring for airtight maintenance fitted into the outer periphery of each piston 10.11, and the reference numeral 2
0 is each center hole 16, 5A of the piston 11 and the support plate 5
This is an O-ring for airtightness that is fitted into the inner circumference of the

The working fluid port 8 communicates with a second working chamber C2, and this second working chamber C2 communicates with the first working chamber C1 via a fluid passage 21 in the piston shaft 15. Further, the working fluid port 9 communicates with the third working chamber C3.

Next, the operation of the piston-type swing actuator configured as described above will be explained.

First, a pressurized working fluid consisting of air or hydraulic oil is supplied from the working fluid port 8 to the second working chamber C2 as shown by the solid arrow.
When the working fluid in the third working chamber C3 is forcibly discharged to the outside from the working fluid port 9 as shown by the dotted arrow, the pressurized fluid in the second working chamber C2 arrow P1 acts on the inner surface of the inner piston 11 in the cylinder tube 1 to move the piston 11 away from the output shaft 2.
direction (outward direction), and the second action chamber C2
The pressurized fluid enters the first working chamber C1 through the fluid passage 21 in the piston shaft 15, acts on the outer surface of the outer piston 10 facing this working chamber C1, and moves this piston 10 toward the output shaft 2. Push it in the direction of arrow P2 (inward) so that it approaches you.

As a result, the rack gear 13a1 of the drive bar 12a is coupled to the inner piston 11 that moves linearly to the left in the cylinder tube 1, and the piston shaft 15 is coupled to the outer piston 10 that moves linearly to the right in the cylinder tube 1.
The pinion gear 14 is rotated by the rack gear 13b of the drive bar 12b coupled through the piston 101 until the stopper piece 6 comes into contact with the stopper 7b.
Rotate clockwise by one outgoing stroke.

This stop 7b also determines the movement stroke of the piston 10.11 so that it does not collide.

Subsequently, as shown in FIG. 6, the pressurized working fluid flows into the third working chamber C3 from the working fluid port 9, and the first working fluid communicates with the second working chamber C2 through the fluid passage 21. When the working fluid in the chamber C1 is forcibly discharged to the outside from the working fluid port 8, the pressurized fluid acts on the inner surface of the outer piston 10 and the outer surface of the inner piston 11 facing the third working chamber C3. These pistons 10, 11 are pushed apart in the left and right direction.

As a result, the outer piston 10 moves linearly in the left direction (Pi force direction) within the cylinder tube 1, and the inner piston 11 is guided by the guide center shaft 4 and moves linearly in the right direction (P2 direction) within the cylinder tube 1. Then, the binion gear 14 that meshes with the rack gears 13a and 13b rotates, and the output shaft 2 is moved so that the stopper piece 6 reaches the stopper 78 on the opposite side.
The piston rotates counterclockwise by 10.11 return strokes until it abuts the piston.

This operation is repeated, and the output shaft 2 performs an oscillating rotational motion.

Next, another example using a lever mechanism as a conversion means for converting the linear reciprocating motion of the piston into an oscillating rotational motion will be described in the seventh example.
This will be explained based on the diagram.

In this embodiment, a lever 22 is fixed to the center of the output shaft 2, and a bottle 24 is inserted into a long hole 23b formed at the rear end of the lever 22 and inserted into the drive bar 12b on the rear side.
b loosely fits into the elongated hole 23 formed at the front end of the lever 22.
A bottle 24a installed in the front drive bar 128 is loosely fitted into the portion a.

In this configuration, when pressurized fluid flows into the second working chamber C2 from the working fluid port 8, each piston 10.11 receives driftwood pressure and approaches the inside of the cylinder tube 1 based on the same operation as described above. The drive bar 1 on the rear side moves in a straight line like this.
The lever 22 connected to the bins 24a and 24b rotates clockwise due to the straight movement of the drive bar 2b to the right and the movement of the front drive bar 12a to the left, so that the output shaft 2 is connected to each piston. Rotate clockwise by a forward stroke of 10.1 units.

Further, when pressurized fluid flows into the third working chamber C3 from the working fluid port 9, each piston 10, 11, as shown in FIG.
The drive bar 12b moves linearly to the left due to the linear movement in the direction of separation, and the drive bar 12a moves linearly to the right to rotate the lever 22 counterclockwise. Rotate counterclockwise by .11 return stroke.

This operation is repeated, and the output shaft 2 performs an oscillating rotational movement.

Next, another embodiment using a cut choke as the converting means will be described with reference to FIG. 9.

In this figure, a scuttle choke 25 is fixed to the output shaft 2, and a pin 27b implanted in the drive bar 12b on the rear side is loosely fitted into a slit 26b formed at the rear end of the scuttle choke 25. A pin 27a implanted in the front drive bar 12a is loosely fitted into a slit 26a formed at the front end of the scuttle choke 25.

In this configuration, when the pressurized fluid flows in from the working fluid port 8, the linear movement of each piston 10.11 in the approaching direction causes the drive bar 12b to move linearly to the right, and the drive bar 12a to move to the left. Move straight to the pin 27a
, 27b rotates clockwise, and the output shaft 2 rotates clockwise by the outward stroke of each piston 10.11.

In addition, in the operation in which pressurized fluid flows in from the working fluid port 9,
As shown in FIG. 10, as the pistons 10 and 11 move linearly in the direction of separation, the drive bar 12b moves linearly to the left, and the drive bar 12g moves linearly to the right, causing the cut choke 25 to move linearly to the left. It rotates counterclockwise, and the output shaft 2 rotates by the return stroke of each piston 10, 11.

This operation is repeated, and the output shaft 2 performs an oscillating rotational movement.

Next, a swing actuator having a single-acting type configuration in which pressurized working fluid does not flow into the third working chamber C3 is installed in the eleventh working chamber C3.
This will be explained based on the diagram.

This swing actuator has a coil spring 28 disposed between the outer piston 10 and the inner piston 11, which acts as a spring force so as to push and spread the space between the pistons 10 and 11. Also, a third action chamber C in which the coil spring 28 is arranged.
An opening 9 communicating with the opening 3 is open to the atmosphere.

In this configuration, when the pressurized working fluid flows into the second working chamber C2 from the working fluid port 8, both pistons 10 and 11, which receive fluid pressure based on the same operation as described above, move to the coil spring 2.
8, the output shaft 2 rotates clockwise by the outward stroke of the piston 10.11. At this time, the third action chamber C3
The air is pushed out by the piston 10.11 and discharged to the outside through the opening 9.

Subsequently, the supply of pressurized fluid from the working fluid port 8 is stopped, and the working fluid in the first working chamber C1, which communicates with the second working chamber C2 through the fluid passage 21, is forced to the outside through the working fluid port 8. When the outer piston 10 and the inner piston 11 are ejected, the elastic force of the coil spring 28 causes the outer piston 10 and the inner piston 11 to move linearly within the cylinder tube 1 so that the distance between them increases. Rotate counterclockwise.

This operation is repeated, and the output shaft 2 performs an oscillating rotational motion.

Next, a swing actuator having a single-acting type configuration in which pressurized working fluid does not flow into the first and second working chambers CI and C2 will be explained based on FIG. 12.

In this swing actuator, a spring housing housing 30 is airtightly fixed to the side of the cylinder tube 1, and between the inner wall of the housing 30 and the outer piston 10,
That is, a coil spring 29 that elastically biases the outer piston 10 toward the output shaft 2 (inward) is disposed in the first action chamber C1. Further, the opening 8 communicating with the second action chamber C2 is
open to the atmosphere.

In this configuration, when pressurized working fluid flows into the third working chamber C3 from the working fluid port 9, the outer piston 10 receives fluid pressure based on the same operation as described above, and moves to the left against the coil spring 29. At the same time, the inner piston 11 moves straight inside the cylinder tube 1 in the right direction.
The output shaft 2 rotates counterclockwise by the stroke of the piston 10.11. At this time, the air in the first working chamber C1, which communicates with the second working chamber C2 through the fluid passage 21, is pushed out by the piston 10.11 and discharged to the outside through the opening 8.

Subsequently, when the supply of pressurized fluid from the working fluid port 9 is stopped and the working fluid in the third working chamber C3 is forcibly discharged to the outside from the working fluid port 9, the outer piston 10 moves against the coil spring 2.
Since the output shaft 2 is pushed by the elastic force of the piston 9 and moves straight to the right in the cylinder tube 1, the output shaft 2 rotates clockwise by the stroke of the piston 10.11. At this time, the inner piston 11 is connected to the pinion gear 14 and the rack gears 13a and 13b.
As a result of the engagement, the piston 1 moves straight in the cylinder tube 1 in the right direction so as to approach the outer piston 10.

This operation is repeated, and the output shaft 2 performs an oscillating rotational motion.

Next, still another embodiment shown in FIG. 13 will be described.

In this embodiment, a cylinder tube 1 with a piston 10, 11 assembled thereon is hermetically fixed to one side of a housing 3 that houses an output shaft 2, and a piston 32 and a coil spring 33 are housed in the other side of the housing 3. cylinder tube 3
1 is airtightly fixed.

Piston 32 assembled inside cylinder tube 31
The tip of the drive bar 12b on the rear side is coupled to the rear inner surface of the drive bar 12b. As a result, the outer piston 10 in the left cylinder tube 1 and the piston 32 in the right cylinder tube 31 are connected to the cylindrical piston shaft 15 and the drive bar 12b.
connected by.

Further, the guide central shaft 4 connected to the front drive bar 12a is slidably and airtightly inserted into a center hole 35 of a support plate 34 fixed to the side of the cylinder tube 31.

Further, a working fluid port 8 provided in the center of the housing 3 is connected to a first working fluid port 8 connected to a second working chamber C2 by a fluid passage 21.
It communicates with the action chamber C1. An opening 9 communicating with the third working chamber C3 between the pistons 10.11 in the cylinder tube 1 and an opening 36 communicating with the fourth working chamber C4 formed on the outer surface side of the piston 32 in the cylinder tube 31
both communicate with the atmosphere.

In this configuration, when the pressurized working fluid flows in from the working fluid port 8, the inner piston 11 moves linearly in the left direction inside the cylinder tube 1 due to the fluid pressure applied to the second and first working chambers C2C1. Integral piston 10.32
moves in a straight line to the right as a whole, so the output shaft 2 rotates clockwise by the forward stroke of each piston. At this time, the air in the third working chamber C3 is pushed out by the piston 10.11 and discharged to the outside through the opening 9. Further, the air in the fourth action chamber C4 is pushed out by the piston 32 and discharged to the outside through the opening 9.

Subsequently, when the supply of pressurized fluid from the working fluid port 8 is stopped and the working fluid in the second and first working chambers C2 and CI is forcibly discharged to the outside from the working fluid port 8, the coil spring 33
, the piston 32 moves straight to the left inside the cylinder tube 31, so the output shaft 2 rotates counterclockwise by the return stroke of the piston. At this time, the piston 11 moves linearly to the left inside the cylinder tube 1 due to the rotation of the output shaft 2, and returns to the home position.

This operation is repeated, and the output shaft 2 performs an oscillating rotational motion.

〔Effect of the invention〕

As explained above, according to the present invention, during the forward linear movement of each piston, the energy of the first and second working chambers can be received by the outer surface of the outer piston and the inner surface of the inner piston, respectively.

Further, during the backward linear movement of each piston, the energy of the third working chamber can be received by the inner surface of the outer piston and the outer surface of the inner piston.

Therefore, in the linear reciprocating motion of each piston, the energy of the action chamber can be received with twice the area of the piston compared to a conventional swing actuator, so twice the output torque can be obtained on the output shaft, and the size is small. This makes it possible to realize a high-output piston-type swing actuator.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of a piston type swing actuator according to the present invention, FIG. 2 is a plan view of FIG. 1, and FIG.
The figure is a front view of Fig. 1, Fig. 4 is a sectional view taken along the line A-A of Fig. 2, Fig. 5 is a sectional view taken along the line B-B of Fig. 3, and Fig. 6 is a state in which the next operation has been carried out. 7 is a sectional view showing another embodiment in which a lever mechanism is used as a means for converting linear reciprocating motion into rotational motion, and FIG. 8 is a sectional view showing a state in which the next operation has been carried out. FIG. 9 is a cross-sectional view showing yet another embodiment using a scutchoke mechanism as a means for converting linear reciprocating motion into rotational motion, FIG. 10 is a cross-sectional view showing a state in which the next operation has been carried out, and FIG. 11 12 is a sectional view of yet another embodiment of the single-action type using a coil spring, FIG. 12 is a sectional view of yet another embodiment of the single-action type, and FIG. 13 is a further embodiment of the single-action type. FIG. 14 is a cross-sectional view showing a conventional piston-type rocking actiniator. [Explanation of symbols] 1.31...Cylinder tube 2...Output shaft 3...Housing 4...
Center shaft for guide 5.34...Support plate 5A, 16.3
5...Center hole 8.9...Working fluid port 10.11.32...Piston 12a, 12b...Drive bar 13m, 13b...Rack gear 14...Pinion gear 15...Cylinder Shaped piston shafts 17a, 17b...Cylinder opening 21...Fluid passage 22...Lever 23a, 23b...Long hole 2
4a, 24b, 27a, 27b...Pin 25...Scatch choke 26a, 26b...Slit 28.29.33...Fill spring 36...Opening C1, C2, C3, C4...Operation Chamber S... Cylinder Tl, T2... Rotation stopper Patent applicant Mitsuo Narushima, patent attorney for TiV Valve Co., Ltd. Figure 1

Claims (4)

[Claims] (1) A cylinder tube is provided on one side of the output shaft, an outer piston and an inner piston whose inner surface faces the output shaft side are provided in the cylinder tube so as to be able to reciprocate, and the outer piston in the cylinder tube has a cylindrical shape. One end of the piston shaft is fixed, one end of the cylindrical piston shaft is opened into a first working chamber facing the outer surface of the outer piston, and the cylindrical piston shaft is slidably and airtightly passed through the inner piston. the other end of the cylindrical piston shaft is opened into a second action chamber facing the inner surface of the inner piston, and the other end of the cylindrical piston shaft is provided with a first drive bar extending toward the output shaft. a second drive bar extending toward the output shaft is fixed to the inner piston, and the first and second drive bars have a conversion mechanism that engages with each other to convert linear reciprocating motion into oscillating rotational motion. and the other of the converting mechanism is attached to the output shaft, and the linear reciprocating motion of each piston is converted into an oscillating rotational motion via the first and second drive bars and the converting mechanism to the output shaft. the first through which pressurized working fluid flows in and out.
A working fluid port is provided in communication with the second working chamber and the first working chamber connected by the cylindrical piston shaft, and the second working fluid port through which the pressurized working fluid flows in and out is connected to the outer piston. A piston-type swing actuator characterized in that it is provided in communication with a third action chamber between inner pistons. (2) A claim characterized in that the third working chamber is provided with a coil spring that elastically biases the outer piston and the inner piston in a direction in which they separate from each other, and the second working fluid port is opened to the atmosphere. The piston-type swing actuator according to item (1). (3) The first working chamber is provided with a coil spring that biases the outer piston inward, and the first working fluid port is opened to the atmosphere. Piston type swing actuator. (4) The tip of the first drive bar is fixed to a piston that reciprocates within an auxiliary cylinder tube provided on the other side facing the cylinder tube, and a fourth working chamber is located on the outer surface of the piston. A coil spring is provided on the auxiliary cylinder tube to elastically bias the piston inward, and a fourth coil spring is provided on the auxiliary cylinder tube.
an opening that communicates with the action chamber, and this opening and the second
2. The piston-type swing actuator according to claim 1, wherein the working fluid port and the working fluid port are opened to the atmosphere.